This disclosure relates generally to the usage of grounding cement for power tower installations. More particularly, this disclosure relates to products and techniques for installing grounding cement in an augured hole.
Power is commonly transmitted through overhead power transmission lines which are supported by spaced poles. For some applications, the poles are formed from composite materials. A hole is formed by an auger. The pole is inserted into the hole and disposed in an upright orientation. A ground wire is strung from the top of the pole and extends into the hole. Grounding cement, which comprises Portland cement and carbon materials, is dropped into the bottom of the hole to enhance the grounding.
In conventional installation techniques, the grounding cement arrives at the installation site in bags. The bags are typically opened at ground level and the cement is poured into the augured hole. Grounding cement is ordinarily not mixed with water to form a slurry, but can set over time upon exposure to moisture.
Upon opening the bag, the grounding cement typically emits a cloud-like dust emission which can be hazardous. Installers are typically required to use masks and to cover their skin to prevent exposure to the dust and to prevent migration of the dust into the installers' respiratory systems. Nevertheless, in practice despite known safety hazards and occupational safety requirements, the grounding cement is often handled without the appropriate use of masks and other protective apparel.
In addition, it is common that the hole collects water at the bottom between the time the hole is formed and the time to install the pole. Consequently, the grounding cement actually may not fully descend to the bottom of the hole in its entirely, and consequently, may not provide the optimum grounding function.